Catalytic Properties

Q.

Silver atom has completely filled d orbitals (4d¹⁰) in its ground state. How can you say that it is a transition element?

Q.

A dilute ferrous sulphate solution was gradually added to the beaker containing acidified permanganate solution. The light purple colour of the solution fades and finally disappears. Which of the following is the correct explanation for the observation?

1. ${\mathrm{KMnO}}_4$ is an oxidising agent, it oxidises ${\mathrm{FeSO}}_4$

2. ${\mathrm{FeSO}}_4$ acts as an oxidising agent and oxidises ${\mathrm{KMnO}}_4$

3. The colour disappears due to dilution; no reaction is involved

4. ${\mathrm{KMnO}}_4$ is an unstable compound and decomposes in the presence of ${\mathrm{FeSO}}_4$ to a colourless compound.

Q.

Explain giving reasons :
Transition metals and many of their compounds show paramagnetic behaviour.

The enthalpies of atomisation of the transition metals are high.

The transition metals generally form coloured compounds.

Transition metals and their many compounds act as good catalyst.

Q.

Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following points:

(i) electronic configurations,

(ii) oxidation states,

(iii) ionisation enthalpies, and

(iv) atomic sizes.

Q. $Si{O}_2$ is attacked by which one/ones of the following?

1. HF
2. conc. HCl
3. hot NaOH
4. Fluorine

Q.

What can be inferred from the magnetic moment values of the following complex species?

Example Magnetic Moment (BM)

K₄[Mn(CN)₆] 2.2

[Fe(H₂O)₆]²⁺ 5.3

K₂[MnCl₄] 5.9

Q. Why a body which is coated inside with platinum black , which has a small hole in its wall can act as a black body why not other materials

Q. Which of the following steps occur in mechanism of heterogenous catalysis:

1. Diffusion of reactant(s) to the surface of the catalyst.
2. Adsorption of reactant molecules on the surface of the catalyst.
3. Occurrence of chemical reaction on the catalyst’s surface through formation of an intermediate.
4. All of the above.

Q. Fe, CO, Ni have valuable catalytic property in process involving

1. Organic compound
2. Oxidation
3. Hydrogenation
4. Compounds of Hydrogen

Q.

The transition metal used as a catalyst is:

1. nickel

2. platinum

3. cobalt

4. All of the above

Q. Aluminium is more reactive than iron but aluminium is less easily corroded than iron because:

1. aluminium is a noble metal
2. oxygen forms a protective oxide layer
3. iron undergoes reaction easily with water
4. iron forms mono and divalent ions

Q.

Identify the type of chemical reaction taking place in each of the following:
Barium chloride solution is mixed with copper(II) sulphate solution and a white precipitate is observed.

Q. Match Column – I with Column – II
$\begin{array}{cc}\text{Column - I}& \text{Column - II}\\ a)\left[\right(P{h}_{3}P{)}_{3}RhCl]& \text{p) Zeigler -Natta Catalyst}\\ b)TiC{l}_4+(C_2{H}_5{)}_{3}Al& \text{q) Anti - knocking agent}\\ c\left)\right(C_2{H}_5{)}_{4}Pb& \text{r) Cisplatin}\\ d)\left[PtC{l}_2\right(N{H}_3{)}_2]& \text{s) Wilkinson's catalyst}\end{array}$

1. a- s b-p c- q d- r
2. a-p, b-s, c-r, d-q
3. a-q, b-p, c-s, d-r
4. a-s, b-q, c-r, d-p

Q. 2. How much volume of KCl is involved at N T P from the complete decomposition of 5 gm KClO3

Q. Why the stability of + 2 Oxidation state of chromium more than +2 OS of Cobalt??

Q. Which of the following statement(s) is true for catalytic hydrogenation reaction?

1. The catalytic activity increases from Group 5​ to Group 11 metals.
2. The catalytic activity decreases from Group 5​ to Group 11 metals.
3. Maximum catalytic activity is shown by group 7 - 9 elements​
4. Both (a) and (c).

Q. Match the catalysts to the correct processess:
$\begin{array}{cc}\text{Catalyst}& \text{Process}\\ \text{(A)}TiC{l}_3& \text{(i)}Wackerprocess\\ \text{(B)}PdC{l}_2& \text{(ii)}Zeigler-Nattapolymerisation\\ \text{(C)}CuC{l}_2& \text{(iii)}Contactprocess\\ \text{(D)}{V}_2{O}_5& \text{(iv)}Deaco{n}^{\prime }sprocess\end{array}$

1. (A)-(iii), (B)-(ii), (C)-(iv), (D)-(i)
2. (A)-(ii), (B)-(i), (C)-(iv), (D)-(iii)
3. (A)-(ii), (B)-(iii), (C)-(iv), (D)-(i)
4. (A)-(iii), (B)-(i), (C)-(ii), (D)-(iv)

Q.

Professor Birch discovered a new element in the Pokemon world and he decided to name it Pokemonium.
And he gave this element to a chemistry lab to find its reduction potential. But they reported back with the oxidation potential as +4.0 V
Where in the existing electrochemical series should he place this new element considering the information is genuine?

1. At the top
2. At the bottom.
3. Just before hydrogen
4. Just after hydrogen

Q. Metals are usually used as catalysts belong to:

1. s-block
2. p-block
3. d-block
4. f-block

Q. Which of the following does not corrode when exposed to the atmosphere?

1. gold
2. copper
3. iron
4. silver

Q.

Ag atom has completely filled d orbitals in its ground state then How Ag can be a transition element?

Q. Match the catalysts to the correct processess:
$\begin{array}{cc}\text{Catalyst}& \text{Process}\\ \text{(A)}TiC{l}_3& \text{(i)}Wackerprocess\\ \text{(B)}PdC{l}_2& \text{(ii)}Zeigler-Nattapolymerisation\\ \text{(C)}CuC{l}_2& \text{(iii)}Contactprocess\\ \text{(D)}{V}_2{O}_5& \text{(iv)}Deaco{n}^{\prime }sprocess\end{array}$

1. (A)-(iii), (B)-(ii), (C)-(iv), (D)-(i)
2. (A)-(ii), (B)-(i), (C)-(iv), (D)-(iii)
3. (A)-(ii), (B)-(iii), (C)-(iv), (D)-(i)
4. (A)-(iii), (B)-(i), (C)-(ii), (D)-(iv)

Q.

Can Peroxide be used as a disinfectant?

Q. Give two reactions in which transition metals or their compound acts as catalysts.

Q. Air in an open container is heated from 17°C to 117°C. The fraction of the original amount of air escaped out from the container is

एक खुले पात्र में वायु को 17°C से 117°C तक गर्म किया जाता है। पात्र से वायु की मूल मात्रा का निष्कासित होने वाला प्रभाज है

1. $\frac{29}{39}$
2. $\frac{10}{39}$
3. $\frac{17}{117}$
4. $\frac{10}{29}$

Q. Assertion :Iron(III) catalyses the reaction between iodide and persulphate ions. Reason: Transition metals act as catalysts.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Write down the name of catalyst for the following:
Deacon's process of making $C{l}_2$ from $HCl$.

Q. Transition metals make the most efficient catalysts because of their ability to:

1. adopt multiple oxidation states and to form complexes
2. show paramagnetism due to unpaired electrons
3. form coloured ions
4. form a large number of oxides

Q. Which of the following pair of elements cannot form an alloy ?

1. $Zn-Hg$
2. $Na-Hg$
3. $Fe-Hg$
4. $Hg-Cr$

Q. Match column A (process) with column B (electrolyte).

1. I-Z, II-W, III-X, IV-Y
2. I-W, II-Z, III-X, IV-Y
3. I-X, II-Y, III-Z, IV-W
4. I-X, II-Z, III-W, IV-Y